A key goal at Bay Hill Ranch is to manage soil erosion better. The two parts of this goal are to keep soil on the hills and to encourage vegetation in the riparian areas that will turn them into sponges that hold sediment and water instead of water flowing over bed rock in deep channels. This land has seen some big changes since transitioning from Native American management to tillage, sheep and cattle grazing. We don’t have a lot of information but we can learn and get ideas by guessing at some of the changes.
How Much Soil Has Been Lost?
There are two primary sources of soil erosion on the ranch. They are channel erosion and surface erosion.
Channel erosion is downcutting of various drainages and riparian areas. We can estimate erosion in the drainages by looking at the shapes of creeks. When we see incised channels with steep banks and flood plains above, we can guess that at some point in the past, there was only a small channel and water used to flow out onto the channel. Looking at the volume of the material that would have filled the channels, we can estimate topsoil loss.
There was also tillage and over grazing that has caused a simple reduction in depth of the top soil. Some of this soil was blown away and some flowed into creeks with rain.
There is a particular 13 acre ridge top section on the ranch with very shallow and infertile top soil and flattened edges that suggest that it was heavily tilled in the past. Known crops in the area include small grains, hay and potatoes. Many potatoes were grown in the area during World War II. The bent ripper rusting in a remote field on the ranch may have been used for potatoes.
Over grazing where sheep remove the protective vegetation layer on the soil also caused surface erosion. One corner of the soil around the 150 year old barn on the ranch is down to the bedrock that supports the foundation of the barn. I suspect this area lost 4 feet of top soil from the impact of sheep around the barn over the years.
A Guess at Volume
Below are very rough estimates using a combination of Google Earth, and on ground observations to estimate where historic flood plains were. The very rough estimates suggest that if 400,000 cubic yards of sediment eroded from the Bay Hill Ranch into the 780 acre Bodega Harbor, it would add an average of 4 inches of sediment to the harbor. The actual erosion could be higher than below because this does not include any overall surface erosion or erosion from slides caused by upland erosion and the down cutting of drainages.
Looking at the sediment volume from another angle. There is roughly 4000 acres of watershed draining into Bodega Bay. If that watershed contributed on average 5 inches of soil erosion to the bay which is what our estimates suggest on the Bay Hill Ranch, that deposits a roughly 2 foot layer of sediment in the harbor over 150 years. That is 2.5 million cubic yards of soil moved from the hills to the bay. Dredging 110,000 cubic yards of sediment from the harbor costs $4.4 million.
|Bay Hill Erosion Estimate||Avg Width – ft||Avg Depth – ft||Cross section – sq ft||Length – ft||Volume-cu yd|
|Above Upper Pond|
|Upper main branch||50||25||625||600||13,889|
|Above Lower Pond||80||30||1,200||2,188||97,244|
|Below Lower Pond||70||25||875||3,600||116,667|
|Area – sq ft||Depth – ft|
|Upper tillage area||584,000||2||43,259|
|Bodega Bay||Area – acres||Area – sq ft||Sediment Volume – cu ft||Depth Added – ft|
|Bodega Harbor Area||781||34,000,000||11,186,100||0.33|
There have been major erosion problems on the Bay Hill Ranch for many years. A combination of overgrazing and past tillage from farming have caused tens of thousands of cubic yards of sediment to be move from the ranch into Bodega Bay near Doran Beach. Also, this area had beavers in the past. Beavers would have built and maintained dams on these creeks that would have captured sediment and created productive fish and wetland habitat.
In 1989 the California Costal Conservancy funded a project to construct two sedimentation ponds on the ranch to keep sediment from the creek beds and hills of the ranch on the ranch and out of the steelhead supporting creek and out of Bodega Bay.
The upper pond is full of sediment and has turned into a gravelly wetland environment. We have begun excluding cattle from the flood plain to help the soils convert from gravel to a higher organic matter and more productive wetland environment. This will help the plants capture sediment in the upper flood plan instead of adding more fill to the small pond area.
The lower pond still has good water and significant sediment capacity but captured sediment has established a healthy wetland area in it’s upper reaches which we are now excluding cattle from.
The images below are from the original design for the sedimentation ponds.
Many of these sediment ponds with concrete lined spillways were built in this area. Two of our neighbors at Freestone Ranch have ponds like this that have filled in. There are several problems with this design.
- The concrete has a design life of 50 years and there is no economically reasonable way to remove or replace them. Work in a creek is very expensive because of environmental regulation. It would probably cost hundreds of thousands of dollars to replace them at the end of their lifespan with a more modern design.
- The concrete design is fragile and high flows tend to overflow and undermine the concrete.
- If the dame fails the sediment they have captured can be released quickly in a large and destructive flood event.
- The dam and pond create a fish barrier and prevent the steelhead below the dam from moving into the upper reaches of the creeks.
- They can reduce summer streamflows. Spring water that flows into the pond in the summer may evaporate before it has a chance to reach fish bearing pools in the lower creek.
- Creeks need some sediment and gravel flow to stay healthy and maintain their vegetation. Ponds like these can capture too much sediment and cause the creeks below them to downcut more.
The ponds do keep the soil on the ranch and they do create nice wetland habitat. The modern designs for this kind of work create step pools using large boulders instead of in stream ponds like these. Despite their challenges it is great to have water and to watch the egrets, ducks and blackbirds enjoying them.
The spillway on the lower pond cannot handle large storm flows. The water sheets over the edge of the concrete and the water undermines the concrete spillway as shown in the photos below. We have added redwood boards to direct the water back on the concrete and increase the flow capacity of the spillway. Hopefully this will keep the spillway functioning for many more years. We also hope that our improved grazing practices and work to increase vegetation in the creeks will increase water infiltration and slow runoff rates in large rains and also help protect the spillway.
The stream below the upper pond has continued to down cut so now the spillway has a five foot drop at the bottom end which creates large water forces that increase erosion and undermine the bottom of the spillway. We have added rock and logs to help prevent it from failing over time
This is where the erosion from the ranch delivered it’s sediment. This is the outlet of Cheney Gulch into Bodega Bay. There a small park, bird habitat and the Bodega Bay sewage treatment plant here.
Bodega Bay needs to be dredged regularly so that boats can continue to navigate the harbor. Sediment runoff from the land draining into Bodega Bay. Presumably agriculture in the hills that drain into the bay has been a significant contributor to sedimentation in the bay.
Not many things are as important to life on our planet as water. Building a new pond in California is expensive but its an investment in the land and in the resilience of our community that will last for generations. We were fortunate to have the opportunity to build a new pond on Freestone Ranch. When we bought the ranch, the developer had a proposal to build a 120 acre foot pond that would be filled with water pumped from Ebibias creek to irrigate 300 acres of grapes. Our pond is about 1/10 the size of the proposed pond and the water comes from sheet flow and a road that so there is no negative impact on the creeks and water shed from the pond.
A pond starts with an engineering plan and permits before the bulldozer and the scraper come. Part of the engineering of the pond is the keyway which is a compacted foundation of soil that connects the levy to the underlying bedrock. For our pond the keyway was dug 15′ deep before placing engineered compacted fill back in. It takes a few years for blackbirds, swallows, dragonflies, ducks, geese and other creature to the come to the pond but they are here now. The 12′ tule reeds on the edges of the pond provide great nest sites for the red wing blackbirds.
The ranches need investment in water, fences, barns, roads and corrals to care for the land and the animals. It has been said that before electric fences, a cattle rancher might spend 40% of their work time maintaining and building fences.
The original fences on Freestone Ranch are probably more the 50 years old. On Bay Hill, they may be a bit younger. We have experimented with various types of fence over the years. Our latest design is a simple two wire electric fence for dividing pastures. New calves occasionally slip through but it’s very reliable for the bigger animals. We built 22,000′ feet of two wire electric fence at Bay Hill Ranch in the first two years.
Cattle need water in every pasture you use for rotational grazing. With both Freestone Ranch and Bay Hill Ranch, the cattle drank water direct from creeks and ponds on the ranch before we started managing them. We have installed miles of water lines and many water troughs so we can exclude the cattle from creeks, rotate them through different pastures and provide them clean fresh water. On Freestone Ranch, we have installed water tanks and 12,000′ of water lines over the years. On Bay Hill Ranch we installed 6,500′ of water lines a tank and a pumping system to get water from the main pond to the top of the hill in the first two years there.
We have built an equipment barn and a hay barn at Freestone Ranch. Building barns ourselves makes them affordable for the ranch and helps us learn new skills.
The hay barn provides a place to store hay and keep it at it’s highest quality through the wet winters.
The equipment barn gives us a place to store the tools and materials needed to improve and maintain the ranches.
One of the biggest responsibilities of a land manager is to preserve and improve the soils of the land. Rain and water flow will always create some erosion but our goal is to minimize the erosion and to have the rate of new top soil formation exceed the rate at which our topsoil flows into ours creeks and ocean. Also, areas where water flows and collects can be the most productive and important areas on the ranch for plants and animals. There is more water available in the soil and there is potential for the soils to be deeper and more fertile as the drainage areas collect sediment that flows from the hills. Our goal on the ranch is to have healthy productive vegetation that will slow water flows and capture sediment in all of our drainage areas.
One of the most destructive and easiest to repair erosion features on a ranch is an upland head cut. This is a vertical face of active erosion where there are not enough plants to slow the water and protect the soil. Cattle like wet areas and their concentrated hoof action can create head cuts with poorly managed grazing.
Bay Hill Gully
We are developing our techniques for using organic matter, soil and grass for repairs instead of intense rock armor. This requires more work and attention but we believe it provides a better long term result with less expensive materials. This gully is on a steep hillside but has a small watershed. It’s fed by a seasonal spring so the erosion was probably caused by animals trampling the moist vegetation and exposing bare soil to the flowing water. There are more issues up the hill but its too steep to access with an excavator so we have focused our repair on the bottom section and hope to capture any sediment that flows down the hill before it reaches the creek.
The repair process was to shape the edges of the gully and ensure there was good topsoil in the bottom of the gully. We then added a layer of compost, and fast growing seed. We also layered in some the grass and seed from the top layer removed from the site. This provides native seed bank in the bottom of the drainage. Straw was added to protect the soil from water flow and jute netting holds the straw in place. The rock lines keep the netting and straw in contact with the soil and help keep flowing water spread out to minimize it’s force on the soil. We had watered the completed work to sprout the grass and stabilize the soil. To keep soil stable on a steep hill like this, you need healthy living soil covered with grass. The soil organic matter, roots, fungi and microbe produce a “glue” that holds the soil together against flowing water. By irrigating we give the soil a chance to heal before the rains and cold weather. The site needs to be checked throughout the rainy season and potentially repaired with straw and grass plugs. There is a electric fence around the gully and animals will be excluded while the soil heals.
Freestone Ranch Large Gully
There large gully on Freestone Ranch is probably 50 years old. Small head cuts over time led to a 600′ long gully that sent around 15,000 cubic yards of soil into our creeks. It was fairly stable when we came to the ranch but there was a small active head cut at the bottom of the gully that was starting to work it’s way up. We did a small repair and excluded the cattle with an electric fence and now, the gully is no longer eroding and is full of lush and diverse native vegetation. It’s a favorite place for the deer to rest in the moist soft bottom. There is also a small gully in the upper right of the photo where we did repairs, tree planting and cattle exclusion.
Freestone Ranch RCD Head Cut Repair
Another example is the Gold Ridge RCD head cuts repairs pictured above on Freestone Ranch. The RCD removed topsoil to shape a smooth contour and then armored the area with rock. They also funded materials for an electric fence to exclude the cattle from the area. We have planted willows to encourage vegetation in that rocked area.
Bay Hill Tunnel Gullies
In the photos above from the Bay Hill Ranch, we were able to take some top soil that had been captured in a pond and move it back up to fill the gullies. The upper gully in the photo actually drained into an underground tunnel. The water was flowing into a rodent tunnel that became enlarged over time and caused a head cut and gully to form above. The after photo shows a simple contour but the simple shape means the top soil is staying where it belongs instead of filling in our pond. Our rotational grazing and lower stocking level make the cow trails pronounced in the 2017 photo.
Bay Hill Head Cut
We brought some sediment recovered from a pond and filled in this head cut to keep it from continuing to progress up the hill. There are a few redwood trees planted in the area to see how they will do. It’s a moist area with deep soils so they are doing fairly well but the spot is probably too windy and the small redwood is showing some wind sculpting already.
Bay Hill Small Drainage
This small drainage is in a moist area. It has good diverse native vegetation but cattle and sheep trailing along the moist bottom has created a series of head cuts in the bottom. We repaired the top head cut to keep it from continuing to move up into the top of the drainage.
The River Ranch is west of Round Valley on the Eel River in Mendocino County. The top reaches 4000′ elevation with pines, firs and oaks at the top. As the ranch drops 3000′ down to the river, the vegetation shifts to oaks, maples, madrones, buckeyes, digger pines and native grasses. The incredible trees, grasses and wildflowers are remnants of the stewardship of the Native Americans that called California home for thousands of years. More recently, settlers established multiple homesteads and even a school on the ranch. As the economics of homesteading faded, much of the land in this area was consolidated into larger ranches. Fences, roads and ponds were built to support timber and larger scale cattle ranching in the area. We are working to respect all of the contributions to the land from our predecessors.
Bay Hill Ranch is perched on the hills about Bodega Bay with a creek and watershed that supports steelhead and drains into the bay at Cheney Gulch. The ranch was farmed and heavily grazed by sheep for 150 years. Topsoil on the ranch has blown away and been carried down in the mud flats of Bodega Bay by Doran Beach. We have been caring for the ranch since 2015. The valleys of the ranch have gullies that reach 20 feet below the historic flood plains. Tens of thousands of cubic yards of soil have eroded from the valleys of the ranch into the bay. The northern portion of the ranch and creeks are heavily impacted by farming and invasive eucalyptus trees while the southern portion sustains an impressive ecosystem of native plants and wildlife. Bedrock and two sediment capture ponds were built by the RCD in the mid 80’s have helped stop the flow of soils into the bay but there is still much that we are working to do to improve the vegetation, soils and health of the creeks. The springs on the ranch were a stopping ground for Native Americans returning from Bodega Bay with their shellfish harvest. It’s easy to imagine Indians camped by the spring and eating shell fish and thimble berries.
In 2006 there was an effort to turn the ranch into a rock quarry that was stopped by community protest. The ranch infrastructure was ignored and the land was overgrazed by cattle after that until we started work on it in 2015.
For us, restoration ranching is about restoring a healthy relationship between people and the nature we live in. At Freestone Ranch, our model for ranching is a collaboration with nature where nature supports our needs for food, water, air, beauty and a home and our presence and efforts make the ecosystems around us healthier, more diverse and more productive. The Native Americans who created and tended the landscapes we value are a source of inspiration for us as we work and learn to have positive impacts on the ecosystems we are responsible for.
The plant ecosystems in our area evolved with disturbance. Unlike many trees, grasses cannot voluntarily shed their leaves, so they need something in their environment to return their biomass back to the soil to keep grass plants healthy and abundant. It’s an important process for cycling nutrients, improving soils, and increasing diversity.
As recently as about twelve thousand years ago, there were megafauna like mammoths and giant sloths that ate the grasses, shrubs, and trees. When those large herbivores went extinct, perhaps from human hunting and climatic shifts, fire took primary responsibility for larger scale disturbances. The Native Americans used intentional fire extensively as a tool to manage these landscapes and keep them open and productive for humans and wildlife alike. Today, fire is not a tool we can as extensively and precisely as cattle, but the millennia-old legacy of cyclical disturbance can be continued with cattle, whose physiology and digestive tracts serve as proxies for large animals of long ago.
For us, working with domestic ruminants to keep grasslands open and healthy is not about recreating the past – but rather, using the resources available in the present to support a better future.
Freestone Ranch is our home ranch. It’s mostly grass with trees along the creeks. It’s in the transition zone from the redwood forests to our north and the large ranches and grasslands to the south. It’s between the towns of Valley Ford and Freestone in West Sonoma County. In the late 1800’s it was a dairy. The train passing the ranch and through Valley Ford would have taken milk to the Sausalito ferry on it’s way to the city. Later it was a sheep ranch. In the 80’s a developer subdivided the ranch and sold 10 house lots with a plan to develop the remaining ranch into a vineyard using irrigation water pumped from the creek. We purchased the ranch in 2004 and have been growing grassfed beef for the local community over 10 years here.
Work we do
- Fencing and water troughs – We’ve installed wildlife friendly fencing, and water troughs to implement our rotational grazing program.
- Erosion repairs – Work to repair several gullies and other erosion issues keeps the soil on the ranch and out of our steelhead friendly Ebibias creek and the Estero Americano.
- Rotational grazing – A key goal of our grazing program is to reduce the density of the non-native velvet grass in favor of a more diverse mix of native perennial grasses.
- Invasive plant reduction – We graze, mow, pull and cut to reduce the populations of non native plants like blackberry, cotoneaster, multiflora rose, velvet grass, eucalyptus, and acacia on the ranch.
- Trees – Willows, oaks, madrone, redwood, and wax myrtle are our favorite trees to plant and protect from cattle and deer browsing.
- Barns – We believe in the value of investing rural agricultural infrastructure and have had the opportunity to build a hay and an equipment barn on the ranch.
- Water – Water is key to life and we invest in the health of our creeks and watersheds by fencing cattle out of the creeks, building a stock pond to increase our water resilience and create wildlife habitat, and treating all the water on the ranch with the reverence it deserves.
- Birds – Since we’ve been caring for the ranch, populations of swallows and red wing blackbirds have moved on the ranch. Quail scatter along the road. The raptors appreciate the grass cover that provides habitat for the rodents they depend on for food as they ride the updrafts where the coastal breeze sweeps over our hills.
Buying our beef is a vote of confidence for investing in and restoring neglected and abused agricultural and wildlands land in Sonoma County.